n = int(input())
s = ''
if n >= 30:
  s = 'Yes'
else:
  s = 'No'
print(s) n = int(input()) n int(input()) int input() input s = '' s '' if n >= 30:
  s = 'Yes'
else:
  s = 'No' n >= 30 n 30 s = 'Yes' s 'Yes' s = 'No' s 'No' print(s) print s n = int(input()) int(input()) n s = 'No' 'No' s s = 'Yes' 'Yes' s s = '' '' s
n = int(input())
s = ''
if n >= 30:
  s = 'Yes'
else:
  s = 'No'
print(s)